Launcher tube access door



F85. 1967 J. F. WITHERSPOON ETAL 3,303,961

ZAUNCHER TUBE ACCESS DOOR 4 Sheets-Sheet 1 Filed Sept. 9, 1964 FIG. 2

INVENTORS JOHN E W/ T HE RSPOON EAR/VEST R. FOREMAN ATTORNEY Feb. 14, 1967 J. F. WITHERSPOON ETAL 3,303,961

LAUNCHER TUBE ACCESS DOOR Filed Sept. 9, 1964 4 Sheets-Sheet 2 I Feb 1967 J. F. WITHERSPOON ETAL 3,303,961

LAUNCHER TUBE ACCESS DOOR 4 Sheets-Sheet 3 Filed Sept. 9, 1964 FIG. 6

Fell 1967 J. F. WITHERSPOON ETAL 3,303,961

' LAUNCHER TUBE ACCESS DOOR Filed Sept. 9, 1964 4 Sheets-Sheet 4 United States Patent 3,303,961 LAUNCHER TUBE ACCESS DOOR John F. Witherspoon, Mountain View, and Earnest R.

Foreman, Saratoga, Califi, assignors, by mesne assignments, to the United States of America as represented by the Secretary of the Navy Filed Sept. 9, 1964, Ser. No. 395,342 8 Claims. (Cl. 22040) This invention relates to an access door for a missile launching tube and to the manually operated mechanism for opening and closing the same.

In the past, access doors for missile launching tubes have ben operated mechanically, hydraulically or electrically, and which mechanism was combined with an emergency manually operated system which was often inadequate. The manual system was designed to be used only when the other system failed. To manufacture a door having the two systems was costly and time consuming. The access door is used, generally for maintenance and inspection, and at times when there is no hurry. It is not a cog in the sequence of firing a missile and has no function to perform which makes it necessary to operate in synchronism with other pieces of mechanism. The door could be made much less expensive and serve the same function if the only mechanism for operating it was manually operated.

Three manually operated access door mechanisms on the launcher tube, in line with access doors on the outer tube, permit entry to the missile. The two lower door mechanisms provide access to the missile second stage jetevators and interstage equipment. The upper door mechanism provides access to the missile guidance package and the forward equipment section of the missile. A switch on each door mechanism indicates to the launcher control panel, whether or not the door is locked. The switch also interlocks control circuits to prevent hatch opening or launcher pressurization if a door is unlocked.

All launcher tube access door mechanisms are identical consisting principally of a door, clamping ring, gear segment, wrench and switch assembly, yoke assembly, opening and latching assembly guide rack and cam. As these door mechanisms are identical only one will be described in detail.

It is therefore the purpose of this invention to provide an access door for a missile tube which is completely manually operated.

It is another object of the present invention to provide, either integral with the tube or securely attached thereto, a door frame which serves as a housing for certain necessary parts of the door mechanism and cooperates with other parts in the opening, closing and sealing of the door.

It is an object of the present invention to provide a door which through manual manipulation may be moved from a closed position to an open position with its path of travel substantially parallel to the surface of the launch ing tube.

It is another object of the present invention to provide a double yoke hinge which will allow the door to move in translation rather than along an arcuate path.

It is a further object of the present invention to provide a seal serving to provide a watertight juncture between the door and the tube.

It is a further object of the invention to provide a clamping ring engaging the door frame and the door to clamp the door securely against the sealing means.

It is another object of this invention to provide a safety mechanism which will indicate the release of the clamping ring during the door opening operation arTd will actuate mechanism which will prevent the tube from being pressurized while the clamping-ring is in released position.

It is a further object of the present invention to provide a guide means for insuring the door following a predetermined path in the opening operation, which path is first normal to the axis of the tube and then substantially parallel to the tube wall surface.

It is a still further object of the present invention to provide an access door which is completely manually operable from a closed, sealed position to a completely open position beyond the confines of the door frame and substantially parallel to the surface of the tube.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 is a perspective view of an access door mounted on the launcher tube;

FIG. 2 is a similar view enlarged and taken at a different angle;

FIG. 3 is a detailed view of the clamping ring rotation gear;

FIG. 4 is a view of the double yoke hinge;

FIG. 5 is an exploded view of the handle and the door latch;

FIG. 6 is a cross sectional view of the clamping ring rotation gear and includes the upper section of the door;

FIG. 7 is a detail view, partly in section, of the door guide block;

FIG. 8 is a bottom plan of the guide block shown in FIG. 7;

FIG. 9 is an exploded view of the door and clamping ring.

Referring to the drawings in detail wherein like parts are designated by like numerals, a missile launching tube 12 is illustrated having an integral door frame 13.

The door frame 13 is formed with a door opening, a retaining ring 14, a switch and plunger housing 15 and has secured to it an arcuate rack 16 and a cam 17. Also attached to the tube wall surface adjacent the frame are bosses 18 for supporting the hinges of the door.

The retaining ring which is part of the door frame is formed with alternate flanges and cut-out portions 21 and 22 respectively. On its inner diameter it is further formed with an inner annular recess 23 and an outer annular recess 24. The inner recess forms an annular seat for a clamping ring 25.

The clamping ring is a rotating part formed with a plurality of dogs 26 on its inner diameter and with a plurality of cutout portions 27 and flange like sections 28 arranged alternately on its outer diameter. The clamping ring has a gear section 29 secured to it which gear section is engaged by a pinion 31 to impart rotation to the clamping ring. This rotation is through a small are, which is sufficient to engage or to disengage the dogs of the clamping ring with the door. Between each of the dogs -a recessed portion 32 provides a release for the door.

The door 30 is a casting formed with a plurality of lugs 33 on its outer diameter. These lugs are engaged by the dogs of the clamping ring, the engaging surfaces being relatively camrned so that continued engagement of the dogs with the lugs during the rotation of the clamping ring will move the door tighter against the door frame. The lugs 33 are slightly smaller than the recessed portions 32 to permit the lugs to pass the clamping ring in the opening operation. The door is further formed with a pair of bosses 35 for hingedly supporting the door and with a second pair of bosses 36 located at the bottom of the door for hingedly supporting a link arm 37. The edge of the door is beveled and formed with an annular groove for an O-ring 38 which engages a section of the door frame toeffectively seal the door. Attached to the door on its inner side is a plastic insert 39 curved to conform to the curvature of the inner wall of the missile launching tube 12. This insert provides a smooth surface which will not interfere with the travel of the missile during the launching operation. 7

The hinge mechanism which permits the door to follow a path which is first normal to the longitudinal axis of the launching tube and then substantially parallel to the surface of the tube consists. of a pair of y-okes 41 and 42. These yokes are substantially identical and are supported for rotation by means of pins 45. The ends 44 of the yoke members are bored to receive the pins which are also carried in the bosses 35 to support the door on the yoke member 41. In a like manner the arms of the yoke 42 are bored to receive pins which are also carried by the yoke 41 to give the two yoke members relative arcuate movement. The yoke member 42 is supported by pins carried by bosses 18 located on the surface of the tube 12 adjacent the door frame to permit that yoke 42 to swing relative to the tube. This particular type of hinge permits the door to be moved outwardly of the door frame and then to move substantially parallel to the tube wall surface. This movement is necessary as the launching tube is itself enclosed within another tube with only a small distance between the two tubes. The outer tube is provided with an access door similar in construction to that of the launcher tube, and aligned therewith.

To insure the opening movement of the door, a link arm 37 is attached to the bosses 36 by a hinge pin. This link arm connects the door with a movable guide block 48. Theblock 48 is substantially rectangular in shape and has an inner slot contoured to fit the arcuate rack 16 which is secured to the surface of the tube slightly below and to the side of the door frame. The rack has associated therewith the curved cam 17 whichis spaced therefrom to permit the guide block to pass with its rear 37 and carries at its end the cam follower 53. Carried in the lower section of the block a latch 54 engages the teeth of the arcuate rack and is released from its engaged position by a cable 56 extending from the block'to a trigger 57 carried by a handle 58. In its engaged position the latch 54 holds the door at any position. Ordinarily the latch is held in its engage-d position by means of a spring 59 and only released by depression of the trigger during the manual operation of opening or closing the door. 7

The handle 58 (FIG. 5) is made up of a substantially C-shaped hand gripping member 63 which is uotatively mounted on a hollow shaft 64 which also supports for rotation the handle supporting arms 65. A cylindrical spacer 66 is carried between the arms 65 and serves as a bearing in supporting the. handle. The C-shaped gripping member is independently rotatable on the shaft to permit it to be moved to a position directly over the arms which position is termed a stowed position as shown in FIG. 1. p

The trigger 57 is pivotally mounted on the top of the gripping member of the handle and is connected to a cable 68 passing through the hollow shaft and connected to the latch 54 carried :by the guide block 58. The trigger extends over the upper portion of the C-shaped gripping member and is depressed by the thumb previously to moving the door. The door is provided with a pin 72 which will overlie the trigger when the handle is in stowed position and hold the trigger so that'the latch is disengaged.

The switch and plunger housing 15 is located at the upper edge of the door frame and serves to house the safety switch 74 and plunger 75. Attached to the plunger is a knob 76 which extends through the housing and is moved through a vertical path to operate the switch. Also mounted in the housing is a pinion 77 which meshes with the gear segment 29 to move the lamping ring in its looking and unlocking movement. The pinion is mounted on a shaft 78 to which a crank 79 is attached. The shaft 78 has a notch located in line with the plunger so that ordinarily the plunger is in position with its end in the notch to lock the shaft 78 against rotation. The crank is located just below the knob so that the knob may be held in released position by one hand while the crank is turned by the other hand. The turning of the crank rotates the pinion which is engaged with the gear segment carried by the clamping ring so that the clamping is rotated through a small are from locked position to unlocked position or vice versa.

Assuming the door to be in the closed and locked position, the manually operated mechanism will function as follows. First the knob is moved to release the plunger from the shaft and the crank is rotated through suificient arc to release the clamping ring. The handle of the door is grasped, taking care to depress the trigger at the same time. Depressing the trigger releases the latch which was engaged with the arcuate rack 16. Pulling on the handle moves the door substantially forward in a translation movement. This movement is slightly toward the hinged side of the door so that the cam follower rides on the spiral surface of the cam. This will rotate the upper section of the guide block about its pivot pin and permit the cam follower to follow the front surface of the cam so that the door now moves substantially parallel to the side wall of the tube. This is necessary because the tube is enclosed by another tube with but slight distance for clearance between them. With the door moved to a desired position the handle is released and the trigger is also released, a spring causing the latch to become engaged with the rack holding the door in an open position.

The above mechanism is completely manually operated; the door is relieved of both weight and complicated mechanism. The manual operation serves all the purposes needed for the limited operation of the door. This construction saves time and money in construction and also in the maintenance and repair of complicated hydraulic or electrical apparatus.

Obviously many modification and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that Within the scope of the appended claims the invention may .be practiced otherwise than as specifically described.

What is claimed is: 1. An access door mechanism for a missile launching tube, comprising: a

a door frame formed as an integral part of the missile tube; 1

a door fitting said door frame;

hinge means mounted on thetube supporting said door so that in the opening operation the door will follow a path which, at first is substantially normal to the longitudinal axis of the tube and then along a path substantially parallel to the cylindrical surface of the tube; sealing means carried by the door; clamping means mounted for arcuate motion on said door frame engaging said door and said door frame to insure the sealing of said door with said door frame;

manually operated means for turning said clamping means;

safety means for indicating the release of said clamping means during the door opening operation; and

guide means attached to said door to insure the door followinga predetermined path during the door opening operation. I

2. An access door mechanism according to claim 1 and including means carried by said guide means for latching the door in any position.

3. An access door according to claim 1 wherein the hinge means for the door comprises a pair of yokes hingedly connected to each other, one of said yokes being mounted on the side wall of the tube and the other of said yokes being mounted on the door.

4. An access door mechanism according to claim 1 wherein the sealing means carried by the door consists in an O-ring.

5. An access door mechanism according to claim 1 wherein the guide means comprises a rack and cam combination secured to the side wall of the tube adjacent the door and below said door and a guide block adapted to engage said rack and said cam, said guide block being connected to said door by a link arm.

6. An access door mechanism according to claim 1 wherein the safety means comprises a switch actuated simultaneously with the rotation of said clamping means and an indicating light located at a remote location from said door.

7. A manually operated door mechanism for a missile launching tube, comprising:

a door frame having a retaining ring, said door and ring being formed integral with the launcher tube;

a substantially plane surface door fitting the opening of said door frame;

means attached to said door on the inside surface thereof to provide an inside door contour matching the inside contour of the tube;

means engaging the retaining ring of the door frame and the door to lock said door in closed position;

sealing means carried by said door so that the door is sealed when in closed position;

manually operated means for rotating the door and retaining ring engaging means from locked to released position; and

means for hingedly supporting said door.

8. A manually operated door mechanism according to claim 7 wherein the means attached to the door comprises a plastic insert shaped to conform to the inside configuration of the launching tube.

References Cited by the Examiner UNITED STATES PATENTS 870,498 11/1907 Egle 22037 1,565,645 12/1925 Hills 220-37 1,688,570 10/ 1928 Williams 220-37 2,379,062 6/ 1945 Brandes 220-+34 X FOREIGN PATENTS 644,944 7/1962 Canada.

THERON E. CONDON, Primary Examiner.

G. E. LOWRANCE, Assistant Examiner. 

1. AN ACCESS DOOR MECHANISM FOR A MISSILE LAUNCHING TUBE, COMPRISING: A DOOR FRAME FORMED AS AN INTEGRAL PART OF THE MISSILE TUBE; A DOOR FITTING SAID DOOR FRAME; HINGE MEANS MOUNTED ON THE TUBE SUPPORTING SAID DOOR SO THAT IN THE OPENING OPERATION THE DOOR WILL FOLLOW A PATH WHICH, AT FIRST IS SUBSTANTIALLY NORMAL TO THE LONGITUDINAL AXIS OF THE TUBE AND THEN ALONG A PATH SUBSTANTIALLY PARALLEL TO THE CYLINDRICAL SURFACE OF THE TUBE; SEALING MEANS CARRIED BY THE DOOR; CLAMPING MEANS MOUNTED FOR ARCUATE MOTION ON SAID DOOR FRAME ENGAGING SAID DOOR AND SAID DOOR FRAME TO INSURE THE SEALING OF SAID DOOR WITH SAID DOOR FRAME; MANUALLY OPERATED MEANS FOR TURNING SAID CLAMPING MEANS; SAFETY MEANS FOR INDICATING THE RELEASE OF SAID CLAMPING MEANS DURING THE DOOR OPENING OPERATION; AND GUIDE MEANS ATTACHED TO SAID DOOR TO INSURE THE DOOR FOLLOWING A PREDETERMINED PATH DURING THE DOOR OPENING OPERATION. 